Clamshell thrust reversers on gas turbine engines have to fulfill at least two functions. A first function is to provide an exhaust nozzle for the direct thrust generated by the engine while thrust reverser is stowed. A second function is to redirect the engine thrust in order to provide a decelerating force or thrust reversal after landing and while the thrust reverser is deployed.
Since almost the entire flight sequence occurs with the thrust reverser in the stowed position, it is desirable that the thrust reverser does not degrade the direct thrust performance of the engine during flight. Clamshell thrust reverser nozzles are also referred to as target or bucket thrust reversers or thrust reverser nozzles.
While many thrust reverser models have been used successfully for a number of years, there is always a need to provide further improved arrangements.